This invention relates to a swivel assembly, and more particularly to a swivel assembly for rotatably mounting an object, such as a boat seat, on a support structure, such as a boat thwart.
The swivel assembly of this invention represents an improvement over conventional boat seat swivel assemblies of the type including a base plate which may be detachably secured to the thwart of a boat, an opposing swivel plate which mounts a boat seat for rotation relative to the base plate, bearings between the opposing inner faces of the plates, and a fastener extending through axially aligned holes in the plates for drawing the plates against the bearings and defining an axis about which the swivel plate rotates. Reference may be made to U.S. Pat. Nos. 3,113,804, 3,789,444 and 3,821,825 showing swivel assemblies of this type.
As manufactured, the prior art swivel assemblies have had a resistance to rotation which is sufficient to prevent the boat seat from turning indiscriminately (as during the ordinary slight rocking action of a boat) but is not so great as to prevent the user from readily swivelling the seat when he desires to do so. However, with usage of the boat seat, the resistance tends to decrease, and there has been no satisfactory provision for enabling adjustment of the resistance to compensate for this decrease. While some assemblies have a nut-and-bolt fastener, tightening of the fastener to draw the swivel plate into more forceful engagement against the bearings to increase the resistance to rotation is difficult if not impossible. This is because access to the fastener for the purposes of tightening it is normally blocked by the boat seat, which, if not permanently secured to the swivel plate, is usually difficult to remove. Turning the fastening element merely from the outer face of the base plate, which is accessible upon removal of the swivel assembly from the boat thwart, simply results in the nut and bolt turning together as a unit.